The Great Lakes constitute a unique resource that faces challenges as communities continue to develop around them. Protecting the Great Lakes environment is vital to the economic, social and ecological wealth not just of the region, but of the continent as a whole. For residents of the Great Lakes Basin, and those beyond, understanding the issues facing these vital resources is becoming more and more urgent. Pollution Probe’s series of Great Lakes Fact Sheets is intended to advance that understanding and create a context for public discussion and action, at both the institutional and individual level. The Fact Sheets look at some of the key challenges affecting the future of the Great Lakes and align with important issues under the Great Lakes Water Quality Agreement (GLWQA) and other initiatives.